Harvard Grid Computing Project Discovers 20k Organic Photovoltaic Molecules 125
Lucas123 writes "In June, Harvard's Clean Energy Project plans to release to solar power developers a list of the top 20,000 organic compounds, any one of which could be used to make cheap, printable photovoltaic cells (PVCs). The CEP uses the computing resources of IBM's World Community Grid for the computational chemistry to find the best molecules for organic photovoltaics culled the list from about 7 million. About 6,000 computers are part of the project at any one time. If successful, the crowdsourcing-style project, which has been crunching data for the past two-plus years, could lead to PVCs that cost about as much as paint to cover a one-meter square wall."
The big thing here is that they've discovered a lot of organic molecules that have the potential for 10% or better conversion; roughly equivalent to the current best PV material, and twice as efficient as other available organic PV materials.
Organic compounds (Score:4, Insightful)
Yes, it could lead to an organic compound that could do that. It could also lead to an organic compound like the one recently installed into BMWs that, when exposed to fire, converts in an aerosol of the deadliest acid known to man. It was marketed as a "green" alternative to existing refridgerants... and it was approved by the EPA. Twenty thousand molecules sounds impressive -- but the odds of finding one that meets safety requirements and is still effective isn't good. Pharmaceutical companies test thousands of compounds every year... and very, very few of those find a medical application. It's the same story here.
So yes, good first step. Good exploratory research. Don't get your hopes up.
Re:Organic compounds (Score:4, Insightful)
Re:Organic compounds (Score:5, Insightful)
That HF production scenario involved Daimler spraying HFO-1234yf over a burning hot engine block.
Okay, am I the only one that thinks that putting a chemical that, when exposed to high heat or fire, converts to one that can cause death if it comes in contact with a patch of skin smaller than the palm of your hand for a few seconds in a car's engine compartment is a really dumb idea? In the event of a front-end collision, you've got shit spraying and leaking everywhere, smoke, flames, people dead, dying, or injured... and you're suggesting that we should introduce into an already inherently dangerous situation for first responders to walk into... the risk of exposure to an airborn acid that can kill them if they come in contact with it and likely wouldn't know at the time they did?
I'm sorry, but I'm with Congress on this: The woman that approved this was a flaming retard that, on no account, should be put in a position of authority over approving other compounds that could potentially save a company a few bucks at the expense of people's lives and health.
Re: (Score:2)
Re: (Score:3)
Depends on concentrations. Water will kill you in high enough quantity. HF is bad, but how much was being produced? How much of this compound would be put in the car? Look hard enough and you'll find just about everything in an uncontrolled combustion product.
Re: (Score:1)
You're such a queef.
Re: (Score:1)
The woman that approved this was a flaming retard...
I see what you did there
Re: (Score:2)
Flaming retard? Or one foot in the revolving door to whatever company invented the stuff?
Re: (Score:1)
What a horrible metaphor. One foot in a revolving door generally gets chopped off, or at least results in a broken ankle.
Re: (Score:2)
Re: (Score:1)
Steel-ankle boots? Even steel-toe shoes wouldn't help.
Re:Organic compounds (Score:5, Interesting)
Seeing as the current refrigerant we use will have equally BAD results if tested in this manner, I wouldn't go nailing anyone to any crosses just yet.
Don't believe me? Run out, buy a can of air duster, make sure you are in a room without much air circulation, turn the can upside down and light the resulting liquid spray on fire. Breath in REAL deep.*
They both make into Hydrogen Fluoride when burned, just add water for your dreaded hydrofluoric acid. Hey, wait a minute, aren't your lung tissues made up of lots of water?
To further make a point: The Dymler engineers mixed the HFO1234yf with compressor oil to increase its burning potential, then sprayed it over a large area on a hot engine block. In our experiment up top we ignited pure R-152a with nothing but a Bic lighter. Food for thought.
*Don't do this.
Re: (Score:2)
If you read the article, it appears that DuPont the chemical manufacturer is the one pushing it, because it's patents on R666 (or whatnot) are about to expire. it was approved via the SNAP process because based on Duponts documentation that it was supposedly safer for the environment. Mercedes own testing caught this flammability/poison issue and recalled every single car it made that used it. So far 2013 Cadillacs and Toyotas are still using it.
I'm not sure how much of this "approval" you wish to pin
Re:Organic compounds (Score:5, Interesting)
Now, I'm not particularly good with metric, nor am I particularly experienced with engine repair (having done nothing more complex than replacing a water pump), but I would think 500C is a bit unusual for an engine to operate at. That's roughly 900F, well above the melting point of, say, lead, and getting close to that of aluminum or magnesium.
According to some brief googling, the typical operating temperature for an engine is under 250F (120C), and gasoline auto-ignites at 280C (540F). So by the time your engine block has reached 500C, you should already have run a good ways away.
Not to mention that, just by the name, tetraflouropropene sounds like a hard chemical to aerosolize, which is also a condition needed for it to release HF.
So to recap:
You first need to get your engine block to a temperature far beyond what it's designed to handle. Then you need to be in a crash violent enough to aerosolize a decent-sized organic compound, *and* that aerosol has to land on that engine. Finally, all the above has to happen in sufficient quantities to produce a dangerous amount of HF gas, which I will note is not quite as holyfuckballswereallgonnadie lethal as you seem to think (it is very dangerous, and rightly feared [corante.com], but you aren't going to die from a milliliter of it).
Yeah, I'm fine with that. Can't be much more dangerous than gasoline, which can kill you under far less unusual circumstances.
Re:Organic compounds (Score:5, Informative)
You first need to get your engine block to a temperature far beyond what it's designed to handle.
As I understood the point, they mixed this stuff with oil and then sprayed that mixture over the engine block. The hot engine ignited the oil and the burning oil reached the required temperature, presumably.
Re:Organic compounds (Score:5, Informative)
but I would think 500C is a bit unusual for an engine to operate at. That's roughly 900F, well above the melting point of, say, lead, and getting close to that of aluminum or magnesium.
If you pop open the hood and look along the sides of the engines, you'll notice that even though your block is aluminum, your exhaust manifold is not. The operating temperature of that will vary from 500 to 1000F for a V6 or V8. It will be higher if it is a rotary engine, or turbo-charged. A turbo-charger works by taking the pressure of the exhaust and using that to drive a turbine that compresses air and feeds it into the intake -- as a result, the exhaust will be at a much higher pressure, typically 9-12 PSI, and that results in the excess heat not dissipating as quickly. 1000F is easily attainable in a turbo-charged engine, like those typically found on the higher-end vehicles this refrigerant was/is installed in.
So by the time your engine block has reached 500C, you should already have run a good ways away.
As indicated earlier, the engine block is not the only source of heat under the hood, nor is it the hottest location. Also, the ignition temperature of gasoline can be much lower than 280C -- it can be as low as 232C (495F) [hypertextbook.com].
tetraflouropropene sounds like a hard chemical to aerosolize, which is also a condition needed for it to release HF.
It is in a closed loop refrigeration system. The typical pressures for the "high" side of a typical system is 200-350 PSI. Needless to say, a leak in the system would result in already-heated liquid that is designed to vaporize at 15-25 PSI being released into the atmosphere (at zero PSI)... which makes converting it to a gaseous state a simple matter of poking a hole somewhere in either loop; Though it would be somewhat more disasterous on the "high" side of the compressor.
So to recap:
Your understanding of physics is based on incorrect assumptions, and is incomplete as well.
Can't be much more dangerous than gasoline, which can kill you under far less unusual circumstances.
Yes, if you drink it I suppose. But many people have been doused in gasoline and unless they are lit on fire, find that it simply stinks and itches. And in many cases, people have survived being burned by gasoline spills that have caught fire. The same can not be said of anyone exposed to hydrofluoric acid. The CDC [cdc.gov] has a few things to say about it... namely that it can be used as a chemical weapon and is exceptionally toxic and fatal even in small amounts. Gasoline on the other hand...
Re: (Score:2)
It is in a closed loop refrigeration system. The typical pressures for the "high" side of a typical system is 200-350 PSI. Needless to say, a leak in the system would result in already-heated liquid that is designed to vaporize at 15-25 PSI being released into the atmosphere (at zero PSI)... which makes converting it to a gaseous state a simple matter of poking a hole somewhere in either loop;
So it will evaporate, not aerosolize?
Can't be much more dangerous than gasoline, which can kill you under far less unusual circumstances.
Yes, if you drink it I suppose. But many people have been doused in gasoline and unless they are lit on fire, find that it simply stinks and itches.
Let's keep the comparison apples to apples, and either note that being doused in a fluorohydrocarbon will probably do little more than to cool you down a bit; or that being doused in carbon monoxide is not exactly the start of a good night on the town, either.
And in many cases, people have survived being burned by gasoline spills that have caught fire.
We don't know how that compares to this compound, all we know is that, under the right circumstances, it can produce HF, while the same can be said of gasoline and CO.
Re: (Score:2)
So it will evaporate, not aerosolize?
Are you really this stupid? Do you not understand how gasses and liquids behave when subjected to sudden pressure changes? I can boil water by simply throwing it in a vaccum...
Let's keep the comparison apples to apples, and either note that being doused in a fluorohydrocarbon will probably do little more than to cool you down a bit; or that being doused in carbon monoxide is not exactly the start of a good night on the town, either.
Dude, it won't "cool you down" a bit. It will, upon being exposed to fire, pass through your skin without leaving any evidence of its passage, and thereupon start to chemically burn your body from the inside out.
We don't know how that compares to this compound, all we know is that, under the right circumstances, it can produce HF, while the same can be said of gasoline and CO.
Exposure to carbon monoxide or gasoline is readily treatable. If I expose you to hydrofloric acid... shooting you in the fac
Re: (Score:2)
Let's keep the comparison apples to apples, and either note that being doused in a fluorohydrocarbon will probably do little more than to cool you down a bit; or that being doused in carbon monoxide is not exactly the start of a good night on the town, either.
Dude, it won't "cool you down" a bit. It will, upon being exposed to fire, pass through your skin without leaving any evidence of its passage, and thereupon start to chemically burn your body from the inside out.
[Bold emphasis mine] Which wasn't what I said. You compared HF production to unburning gasoline, which I pointed out was not the fairest of comparisons, and gave two fairer comparisons.
Exposure to carbon monoxide or gasoline is readily treatable.
To the degree that it doesn't kill you, yes. But then, so is exposure to small amounts of HF (at least skin exposure, I imagine no good way to treat lung exposure exists): Rinsing with water for 12 hours removes most of it*. Admittedly not something I yearn to try, but very few things involved in a car crash is. It is not cle
Re: (Score:2)
Also, in modern cars, the fuel pump is disabled automatically after a crash.
I'm not an expect in car drive-trains either. Panels, sure. Everything else, meh.
Re: (Score:2)
Re: (Score:2)
That HF production scenario involved Daimler spraying HFO-1234yf over a burning hot engine block.
Okay, am I the only one that thinks that putting a chemical that, when exposed to high heat or fire, converts to one that can cause death if it comes in contact with a patch of skin smaller than the palm of your hand for a few seconds in a car's engine compartment is a really dumb idea? In the event of a front-end collision, you've got shit spraying and leaking everywhere, smoke, flames, people dead, dying, or injured... and you're suggesting that we should introduce into an already inherently dangerous situation for first responders to walk into... the risk of exposure to an airborn acid that can kill them if they come in contact with it and likely wouldn't know at the time they did?
I'm sorry, but I'm with Congress on this: The woman that approved this was a flaming retard that, on no account, should be put in a position of authority over approving other compounds that could potentially save a company a few bucks at the expense of people's lives and health.
You sir are a fool. Consider that we tell the paramedics to just let the BMW owners die. Fucking pricks the lot of 'em anyway. Doing the world a favor and you call her a flaming retard? Get a check-up from the neck-up, mate.
Re: (Score:2)
You may want to look in your kitchen cupboard and notice that bottle of bleach. Am I the only one who thinks that storing a compound that so easily produces a deadly war gas that strips the lining of your lungs when mixed with the contents of the bottle of cleaner next to it is a really dumb idea? Don't even get me started on the fool who thought that allowing cables carrying the same deadly electrical current that is used for electrocuting criminals into every home was a good idea.
Daily life is full of po
Re: (Score:3)
Not to be that guy, but I wanted to know more about the acid thing, couldn't find it. It's actually Mercedes, BMW refused to put it in their cars. It also creates an incredibly toxic gas along side the acid.
More here:
http://www.dailymail.co.uk/news/article-2307265/EPA-nominee-tough-questions-approved-new-car-air-conditioner-refrigerant-caused-ENGINE-FIRES-Mercedes-Benz-tests.html [dailymail.co.uk]
Re:Organic compounds (Score:5, Funny)
Can you provide a citation that doesn't come from a fear-mongering rag of an excuse for journalism?
Sure can! [foxnewsinsider.com]
(trollface)
Re: (Score:2)
Can you provide a citation that doesn't come from a fear-mongering rag of an excuse for journalism?
From an SAE presentation:
Risk per vehicle per operating hour
Risk of occupant/former occupant experiencing HF exposure above health based limits associated with an R1234yf ignition event: 3 x 10 -12 power
Risk of occupant being exposed to an open flame due to R1236yf ignition: 9 x 10 -14 power
Industry Evaluation of refrigerant HFO-1234yf [sae.org]
Re: (Score:3)
Those numbers by themselves are useless in predicting the number of cases of exposure per year. Unfortunately, accurate numbers for the hours an average person drives are hard to come by, but by miles it's around 13,476 [dot.gov] per year. Let's high-ball it for the sake of discussion and say the average speed of a motor vehicle is going to be 60 MPH. That means the average driver then spends 224.6 hours in their vehicle.
So the risk to the driver per year would be, er, about 1 in 13.3 million. "Coincidentally" that'
Re: (Score:2)
in the US : approx 350M people / over 30K deaths/year = on the order of 1 in 10,000.
Re: (Score:3)
The problem with Pharma is they need to find a chemical that is effective against the pathogen/disease they are targeting and then make sure it is also efficiently absorbed by the body into the location that the disease/pathogen is so the dose they would need to give to a human are not toxic. The requirements for something like these PV compounds are far lower.
Re: (Score:2)
The requirements for something like these PV compounds are far lower.
Yes, there's no disagreement there. I'm just saying, creating a list of potentially useful molecules is only the first step in the search. Just like it is with "Pharma". Nobody's claiming otherwise...
Am I the only one who read the... (Score:2)
summary and thought polyvinyl chloride when reading "PVC"?
Re: (Score:2)
Roughly equivalent my ass. (Score:3)
Re:Roughly equivalent my ass. (Score:5, Informative)
Try half. High efficiency silicon cells are up to 20%.
The best are now sitting at 44% (http://en.wikipedia.org/wiki/File:PVeff%28rev130307%29.jpg). That doesn't mean cheaper solar cells don't have lots of potential, but it does mean the editors here screwed up again. There are a few other errors in TFS as well, but this one really got me:
could lead to PVCs that cost about as much as paint to cover a one-meter square wall."
Huh? So does this mean a PV coating will will have the same cost per area as paint. Personal expertise tells me no. Does it mean a postage stamp of PV coating will coast as much as a square meter of paint? That's actually more realistic for the midterm future, but the language in TFS shows such a basic lack of understanding of both numbers and units that it's impossible to tell what the editor or submitter really meant to say.
Re:Roughly equivalent my ass. (Score:5, Informative)
Those 44% cells use an optical concentrator, aka magnifying glass, and require a substantial cooling system (concentrating the suns energy 418x creates a lot of heat)
They're also not commercially available, although neither are any cells using one of these 20,000 different molecules.
Re: (Score:2)
Re: (Score:2)
... in a lab environment
Re:Roughly equivalent my ass. (Score:4, Informative)
We haven't used optical concentrators for 40% cells in quite a while. Now we use focused-bandgap absorption and silicon nano-structures to act as waveguides, no concentrator needed.
Re: (Score:2)
You didn't look at that graph did you? The entire top line is triple junction PV cells with a concentrator.
The highest non-concentrator research is 37.8% from a four-junction cell.
If you're doing 40% without a concentrator the National Renewable Energy Laboratory probably wants to hear from you and you're beating the pants off Boeing Spectrolab and Sharp
Re: (Score:2)
Ahem... four-layer passthrough cells with optical waveguides (no lenses) built right onto the cells themselves, each layer harnessing a different bandgap. Top layer rolls red, second green, third blue, fourth UV. They sit on top of my research facility in the UK, and power it. Thank you.
Re: (Score:2)
Still not 40%.
Re: (Score:1)
" but it does mean the editors here screwed up again."
No, it means the editors have pretty much lost any and all geek credential, plus have Alzheimer's, since we've had 20% silicon and high-efficiency cells for more than 5 years and we kept getting stories about them on slashdot.
Seriously, me shit-drunk could do a better job than every editor here combined.
Re: (Score:2)
I think you probably meant to link to this copy of the file instead:
http://upload.wikimedia.org/wikipedia/commons/e/ed/PVeff(rev130307).jpg [wikimedia.org]
Re: (Score:2)
Try half. High efficiency silicon cells are up to 20%.
The best are now sitting at 44% (http://en.wikipedia.org/wiki/File:PVeff%28rev130307%29.jpg). That doesn't mean cheaper solar cells don't have lots of potential, but it does mean the editors here screwed up again. There are a few other errors in TFS as well, but this one really got me:
could lead to PVCs that cost about as much as paint to cover a one-meter square wall."
Huh? So does this mean a PV coating will will have the same cost per area as paint. Personal expertise tells me no. Does it mean a postage stamp of PV coating will coast as much as a square meter of paint? That's actually more realistic for the midterm future, but the language in TFS shows such a basic lack of understanding of both numbers and units that it's impossible to tell what the editor or submitter really meant to say.
I was referring to commercially available cells. Heterojunction cells can get as high as you say under some conditions. I think the 44% is only achieved with a 1000X light concentrating lens. That's not a fair comparison. The 20ish percent is fair because it's commercial flat cells that don't suffer from the HARD TO USE problems that come with the types that only work well under concentrators.
Re: (Score:2)
We *sell* panels with cells over 20%. You can buy them anywhere. *Panel* efficiency is lower, typically 16 to 16.5%. That's because of the space between the cells, reflection off the glass, wiring losses, etc.
Panels are widely selling for about 70 cents a watt. Racking, inverter and wiring adds about the same amount. So even if we reduce the price of the panel by half, that will have an increasingly small effect on the installed cost. However, wiring and racking varies with the area of the system, so any de
one-meter square (Score:2)
could lead to PVCs that cost about as much as paint to cover a one-meter square wall
Another wasted effort. Who has a wall that is only one meter square? And if it costs as much as paint and covers one square meter, wouldn't it also cost as much as paint to cover a more useful size structure?
Re: (Score:2)
Perhaps it costs more than paint if you cover a smaller area as there may be fixed costs for things like power connections.
Re: (Score:1)
The one square meter thing means for the same area, it's just a sensible way to express it. You don't say "my car is cheaper to run for the same distance travelled than yours," you say "I get more kilometres per litre."
Re: (Score:3)
No its not a sensible way to express it.
If it costs the same for one square meter of PVC as it does for one square meter of paint then you just say ...
It costs the same as painting a wall.
Area is irrelevant if it costs the same for equal areas. Did you not take basic math in school? You don't throw in terms that have no useful meaning to the equation just for shits and giggles, which is whats being done here.
You might as well be retarded and say shit like:
It costs the same as paint on planet Earth!
With ca
Re: (Score:1)
With cars, we say 'it gets the better milage' because you aren't actually comparing cost
According to your argument we should say "it gets better distance for a given amount of fuel." Saying "mileage" incorporates the unit "mile" and incorporating a unit to denote a dimension is apparently something you are vehemently opposed to.
Saying "it costs the same as painting a wall" is less accurate than saying "it costs the same per unit area as paint."
I'll just ignore your ad hominem bullshit.
Excuse me (Score:5, Funny)
While I go and file 20,000 patents...
Re: (Score:2)
With all the money you're going to spend filing those patents, why not contribute to the research instead? $20M would help bring the industry a long way :)
http://www.uspto.gov/web/offices/ac/qs/ope/fee031913.htm [uspto.gov]
Please compare apples to apples. (Score:2)
Its all about the colour.. (Score:2)
Transparent conductors? (Score:2)
Don't PV panels require a transparent conductor as a top layer? Something that lets the light through and conducts away the electricity?
Once the side of your house is painted with this stuff, how would you gather the energy?
Cheap photovoltaic molecules is part of the problem. We still need a cheap transparent conductor to gather the generated energy.
Complaints (Score:1)
Misleading statement in TFA (Score:5, Informative)
The current best PV materials have 20% or better conversion rate
Even the garden variety stuffs from China gets you about or above 15% conversion rate
I reckon the organic compounds are better, in the sense that they do not pollute the environment as much, but to that they are "equivalent" to the "best PV material" in terms of conversion rate, tastes a little bit funny to me
Re:Misleading statement in TFA (Score:5, Insightful)
Nitpicking point taken.
However, the other part of the equation, cost, has the potential to make these very attractive compounds. If you could turn the side of your house into a solar panel for just the cost of paining it, this would be a very attractive value proposition. Even if the efficiency was only half that of a conventional PV panel, the cost per watt would be much lower.
Good to see this research.
Re:Misleading statement in TFA (Score:4, Insightful)
Re:Misleading statement in TFA (Score:4, Insightful)
I daresay doing it in a way where you actually get electricity would make the costs go up by a lot more. And depending on how its done it could make the efficiency go down too.
Merely painting your wall with crushed/blended solar panel material won't produce much usable power.
Re:Misleading statement in TFA (Score:5, Funny)
I'll take a wild guess and say they use wires.
Re: (Score:1)
they use metal leads silkscreened onto the surface
That is still a wire, just an more difficult and expensive kind of wire to make and attach.
Re: (Score:2)
After the PVC paint is applied and dried, you have an inkjet printer modified to print on a broad flat surface. It prints a conductive ink pattern, solving the problem.
A refinement to enhance longevity and conductivity would be to have the print head be followed by a laser to sinter the metallic particles into a single monolithic conductor.
Re: (Score:2)
I didn't read anywhere that the PV material was itself a paint, but that the cost per area was similar to that of paint. They could have said Carpet (though the value of carpet varies quite a bit)
Re: (Score:3)
Re: (Score:3)
Some people see the advancement of mankind as something they want to contribute to, even if they don't instantly gain anything other than satisfaction from it.
I, for one, wouldn't mind if somebody makes stacks of money off my contributed CPU cycles. In fact, I'd applaud it if worldwide solar power production would increase because of it.
Re: (Score:2)
I recommend that you use a dictionary to look up the word "volunteer" and note that the definition doesn't include "petty bastard who only works for personal gain" This will save everyone here the trouble of quoting the Princess bride to you.
Re: (Score:2)
I'd be more worried about how long they last. What's the expected lifespan of organic molecules exposed to high levels of UV & heat for the majority of days over a 10 or 20-year period? Although if it's cheap enough, I guess you just strip and re-coat every 3-5 years.
Re:Misleading statement in TFA (Score:5, Interesting)
Indeed. They're probably including labor costs, but still. One gallon of paint covers ~32m^2, * 2-6kWh/m^2/day insolation for a vertical equator-facing surface outside the tropics (relatively constant throughout the year, neglecting cloud cover and other shade sources) * 10% = 6-20kWh/day year round for a one-gallon paint job. Wouldn't have to last long at all to pay for itself.
Re: (Score:3)
Wouldn't just be paint though. You have to somehow paint a base conductor, the organic PV material, and a transparent top-electrode. You also have to segment and set up chains, otherwise the whole thing will kick out like 1V pretty inefficiently.
Re: (Score:2)
Re: (Score:2)
The punchline is you really want to panel it onto foil and then laminate over that or something I suppose. More like wall-paper I guess?
Re: (Score:2)
Reminds me of talking to an environmental cleanup specialist about an oil tank I had that leaked.
I asked if he had any idea what kind of total cost I was looking at, and his answer basically boiled down to, yes, we could study the spill and determine its extent.... but by the time we were done, it would cost a signficant fraction of what its likely to cost to clean up.
(though, for a much larger spill that cost/benefit would flip)
Re: (Score:2)
Nothing so complicated actually - around here paint is sold by the gallon, and the rule-of-thumb is 1 gallon = 350sq ft, which I then converted to real units for doing math.
Misleading question with no answer in above post (Score:2)
Re: (Score:2)
What's misleading about it? No-one knows how long a PV panel made with organic molecule technology will last, so how could I mislead anyone, especially when my point was couched as a query - "what's the expected lifespan....."
Conventional doped silicon PV has a warranty of ~20 years for ~80% of rated output - such as the ones on my roof. That is a reasonable comparison to make - even if "organic" PV doesn't last as long as current technology - say one-quarter of the time - if it costs a similar amo
Re: (Score:2)
I'll explain the trick to the readers. It's misleading because it's bunching together a wide range of materials, thus it will be a very wide range of answers once they are determined (which will take time). To cap it all off the above poster supplies his own disparaging answer (when none are yet available) to imply little or no worth. In other words, a petty and childish trick demonstrating zero respect or interest in the subject matter, just so
Re: (Score:2)
I guess you just strip and re-coat every 3-5 years.
Never paint in the nude.
Re: (Score:2)
Re: (Score:2)
Actually, depending on how you define best (do laboratory samples count?) I think they're past 40% now.
Still, equivalent within a small fraction of an order of magnitude, which is pretty impressive all things considered. IIRC chlorophyll is only 2%-3% efficient*, and it's had billions of years to optimize.
*real-world efficiency - laboratory eficiency is >40% for the narrow band of wavelengths it absorbs.
Re: (Score:2)
Re: (Score:1)
Until the other options improve on that, they're just a waste of investment.
So I'm guessing you don't get investment
Re: (Score:2)
Overall real world efficiency for chlorophyll can vary from 2% up to a whopping 15%, depending upon organism.
PV with 40% conversion rates (Score:4, Interesting)
Actually, depending on how you define best (do laboratory samples count?) I think they're past 40% now
If you read closely on how they achieve the more than 40% efficiency you would see that they are not "1 sun" PV structure
Case in point, Solar Junction ( http://www.sj-solar.com/ [sj-solar.com] ) came out with the "lattice matched 942X" which has 44% conversion rate
That "942X" denotes "942 suns", which means, the PV from Solar Junction is not flat panel type of PV, but rather, achieve its high efficiency with the use of focusing optics
Allow me to quote from http://www.renewableenergyworld.com/rea/news/article/2012/10/solar-junction-does-it-again-sets-new-cpv-efficiency-record [renewableenergyworld.com]
" ... Think of a magnifying glass. Basically, you have a very high performance solar cell that sits at the focal point of these focusing optics. The solar cell converts the photon flux into electrons, and power
Re: (Score:2)
Nothing wrong with that, it's not like they're conentrating 942 times the insolation on it and then measuring efficiency relative to normal insolation. In fact that may be a significant feature since mirrors/lenses are typically far cheaper than photovoltaics, but most photovoltaics can't survive extended exposure to that sort of power flux. So long as this stuff is notably less than 942x as expensive as common PVs it may be a good deal, at least for power plants where more complicated systems aren't near
Re:Misleading statement in TFA (Score:4, Informative)
Re: (Score:1)
It is much simpler. While having a lower conversion rate, they are just so incredibly cheap that you can easily get 10 times as many.
To the point of pollution: they are really awesome. In fact around here (Switzerland) it is a quite common high school chemistry project to create such organic solar cells from TiO2 coated glass and tea leaves - quite a fun project.
Re: (Score:2)
Re: (Score:2)
10% is similar to the best non-crystalline cheap solar cells. You're thinking of the far more expensive type. I can't think of a single large-scale solar utility plant using crystalline silicon. Go read about First Solar [reuters.com]. These are one of the few solar companies still making a profit. Their technology is so much cheaper than the more efficient arrays that literally half of the existing solar production plants will need to close down because they can't compete with First Solar.
Discovering new molecules
Re:Misleading statement in TFA (Score:4, Insightful)
Re: (Score:1)
First solar uses CdTe. Even CdTe and CIGS have better efficiency than 10%. Quoting Wikipedia: In February 2013, First Solar created a cell with an 18.7% efficiency.
The "cheap" solar panels from China used in housing installations are usually crystalline silicon so it is less rare than you seem to think.
Re: (Score:1)
you have no fucking idea what trollable is, you moron.
you think what you're doing is trolling? it's way too fucking lame for that, nor does it mean any of the actual criteria for trolling.
you're just being an unjustifiably arrogant and pretentious smug wanker....if you're still a teenager, your mum might think it's precociously cute (nobody else would).